A deal, expected to be announced soon, would reportedly award Dauman a hefty parting sum of $72 million, a source told Reuters. It comes after Dauman has consistently been among the highest paid CEOs in recent years, according to Equilar, which specializes in executive compensation data.

Dauman has made a total $409.67 million in reported compensation — which includes the grant date fair value of any stock or options awards — since he was named CEO in September 2006. His realized pay during that time — which is the amount earned in cash in the given year, plus the value of shares vested in that year, and gains from exercised options — totals $491.66 million, Equilar said.

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Phillipe Dauman, CEO of Viacom

That means Dauman's 2015 reported compensation of $54.15 million was about 118 percent higher than the $24.8 million he made in 2006. His 2015 realized compensation of $112.39 million was about 4,043 percent higher than 2006, when he was paid $2.71 million.

During that time, Viacom's class A shares have risen about 35 percent.

To be sure, Dauman's pay has fluctuated widely, and 2015 was one of the highest years of pay measured by Equilar. Still, his pay has kept close track with executives at the likes of rival Disney, though Disney's shares have outpaced Viacom's over time.

He was the number 3 highest-paid CEO in 2015, behind CBS's Leslie Moonves, according to Equilar's study with The New York Times. He was the 11th highest-paid CEO at a U.S. publicly-traded company from 2012 to 2014, by Equilar's measure. (Dara Khosrowshahi, CEO of Expedia, took the top spot in 2015.)

Dauman is expected to leave Viacom as part of a settlement with controlling shareholder Sumner Redstone, two unnamed sources told Reuters. The settlement would end a lengthy battle over the direction of the media giant.